Power distributing device is a device that divides one input signal into two or multiple output signals, or is a device that combines two or more input signals into one output signal. Power distributing device is widely used in antenna array, balance power amplifier, mixer, phaser, and so on. Power distributing device contains 3 dB bridge coupler, branch-line bridge coupler, annular bride coupler, and Wilkinson power divider, and the most frequently-used power distributing device is the Wilkinson power divider. However, traditional Wilkinson power divider occupies a large area of printed circuit board (PCB) due to length of the Wilkinson power divider being fourth of the operation frequency. Furthermore, traditional Wilkinson power divider lacks harmonic suppression function. In order to suppress harmonics, filter is needed, and this largely increases the cost. Therefore, a miniaturized power distributing device with harmonic suppression function and low cost is needed.